Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
  • H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
  • H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
  • H01M8/04119—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants with simultaneous supply or evacuation of electrolyte; Humidifying or dehumidifying
  • H01M8/04126—Humidifying
  • H01M8/04149—Humidifying by diffusion, e.g. making use of membranes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
  • B01D63/08—Flat membrane modules
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
  • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
  • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
  • H01M8/04828—Humidity; Water content
  • H01M8/04835—Humidity; Water content of fuel cell reactants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2313/00—Details relating to membrane modules or apparatus
  • B01D2313/08—Flow guidance means within the module or the apparatus
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2313/00—Details relating to membrane modules or apparatus
  • B01D2313/14—Specific spacers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
  • F24F6/00—Air-humidification, e.g. cooling by humidification
  • F24F6/02—Air-humidification, e.g. cooling by humidification by evaporation of water in the air
  • F24F6/04—Air-humidification, e.g. cooling by humidification by evaporation of water in the air using stationary unheated wet elements
  • F24F6/043—Air-humidification, e.g. cooling by humidification by evaporation of water in the air using stationary unheated wet elements with self-sucking action, e.g. wicks
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/30—Hydrogen technology
  • Y02E60/50—Fuel cells

Definitions

• Humidifier module Humidifier module, humidifier, fuel cell system with such, as well as method for humidifying a gas
• the invention relates to a humidifier module for a humidifier in a fuel cell system with a gas-permeable membrane, on one side of which a flow field core defining a flow field is arranged, the flow field core having at least two separating webs between which a channel is formed.
• the invention also relates to a humidifier with a plurality of humidifier modules, a fuel cell system with a humidifier and a method for humidifying a gas in a fuel cell system.
• Humidifiers are generally used in order to be able to effect a transfer of the moisture to the drier medium in the case of two gaseous media with a different moisture content.
• Such gas / gas humidifiers are used in particular in fuel cell devices in which air with the oxygen contained therein is compressed in the cathode circuit to supply the cathode chambers of the fuel cell stack, so that relatively warm and dry compressed air is present whose moisture is suitable for use in the fuel cell stacks for the membrane electrode unit is insufficient.
• the dry air provided by the compressor for the fuel cell stack is humidified by being guided past a membrane that is permeable to water vapor, the other side of which is coated with the moist exhaust air from the fuel cell stack.
• liquid water is produced in the cathode and anode compartments.
• Humidifier can be made comparatively large. At the same time, enough liquid water must be provided for humidification.
• US 2006/147773 A1 describes a humidifier with flow fields that are porous and hydrophilic and can be fixed as inserts in the frame with a seal on the edge.
• the humidifier module is characterized in particular by the fact that the dividers are made of a hygroscopic, water-insoluble material are formed such that a liquid flowing into the at least one channel can be temporarily stored in the hygroscopic separating webs. This thus enables liquid water to be taken up from the fluid flow into the hygroscopic separating web, temporary storage of the liquid water thus absorbed in the hygroscopic separating web and dispensing of the liquid water by evaporation into the fluid or gas flow flowing through the channel.
• liquid water from the gas stream which is usually discharged continuously into the humidifier, can be temporarily stored in the flow field and, if required, evaporated into the gas stream, in particular into the cathode stream, and absorbed by the membrane in order to humidify it.
• the humidifier is stabilized by the at least two separating webs, which preferably support the membrane on both sides.
• the separating webs formed from a hygroscopic material preferably have capillary-active properties, so that the liquid water is absorbed and distributed within the separating web, so that the liquid water is evenly distributed or is evenly distributed within the humidifier.
• the hygroscopic material can for example be a silicate, in particular calcium silicate, or a zeolite.
• the flow field core is surrounded by a hydrophobic frame, or if the flow field core is received in a hydrophobic carrier plate.
• the frame or the carrier plate made of a hydrophobic, i.e. non-water-conducting material prevents water from being transported to the outside and thus seals the flow field from the outside.
• the flow field core can be pressed into the hydrophobic carrier plate.
• a plurality of hygroscopic separators form separate channels, and if the channels are straight and parallel extend towards each other.
• the straight extension of the channels ensures a low pressure loss within the humidifier module.
• the storage capacity of the liquid water is increased by the plurality of separators and the support of the membrane and thus the stability of the humidifier module is improved.
• the large number of channels formed by the separating webs ensure that the fluid flow and the liquid water are guided.
• a plurality of channels formed by hygroscopic separating webs are present, and that the separating webs have at least one deflection.
• the separating webs can be curved or angled.
• the separating webs have multiple deflections. By means of the deflections, the separating webs form areas on which water droplets can be deposited. This increases the separation rate and enables the liquid water to be stored more effectively in the hygroscopic separators.
• the separating webs have deflections along their direction of extension at regular intervals, and preferably parallel to one another. This increases the deposition rate.
• the humidifier according to the invention for humidifying a gas for a fuel cell system with two end plates, on which an inlet for dry gas, an outlet for humidified gas and another source for humid gas and another outlet for a dehumidified gas is formed is particularly distinguished characterized in that a plurality of the humidifier modules already described are arranged between the end plates.
• the advantages and preferred embodiments described for the humidifier module according to the invention also apply to the humidifier according to the invention which is equipped with a plurality of such humidifier modules.
• the advantages and preferred embodiments described for the humidifier according to the invention or the humidifier module according to the invention also apply to the fuel cell system according to the invention which is equipped with such a system.
• a separator is available on the anode side, if an outflow of the separator is fluidically connected to the humidifier and / or if a cathode exhaust line is fluid-mechanically connected to the humidifier on the cathode outlet side. This enables the anode side and / or cathode side accumulating liquid water to be used for humidification, whereby the size of the humidifier can be reduced.
• the method for humidifying a gas in a fuel cell system with a fuel cell stack that is fluidly connected to a humidifier described above comprises in particular the following steps:
• the liquid water is removed from the fuel cell stack on the anode side and / or on the cathode side.
• the liquid water can be removed by actively draining the liquid water the fuel cell stack.
• the discharge of liquid water from the fuel cell stack to fill the separating webs takes place continuously.
• 1 a is a schematic representation of a humidifier module
• Fig. 1 b is a plan view of the humidifier module from Fig. 1 a with geradli nig trained separators,
• Fig. 2 is a schematic representation of a further Befeuchtermo module with separators which have a deflection and
• FIG. 3 shows a fuel cell system with a humidifier having a plurality of humidifier modules.
• FIG. 1a and FIG. 1b show a humidifier module 1 for a humidifier 15 with a gas-permeable membrane 3, on one side of which a flow field core 4 defining a flow field is arranged.
• the flux field core 4 has a plurality of separating webs 5, between each of which a channel 6 is formed.
• the separators 5 are made of a hygroscopic, water-insoluble material, in particular calcium silicate, in such a way that liquid water is removed from a fluid flowing in the channels 6, taken up in the hygroscopic separators 5, temporarily stored there and, if necessary, from evaporation the separators 5 issued who can.
• FIG. 1 b shows that the flow field core 4 is surrounded by a hydrophobic frame 7.
• the flow field core 4 is pressed into a hydrophobic carrier plate.
• the hydrophobic frame 7 of the Flow field core 4 prevents the liquid water from escaping from the flow field core 4 to the outside, so the flow field core 4 is sealed off.
• the rectilinear and parallel extension of the channels 6 enables the fluid flowing therein to be guided in the event of a low pressure loss.
• the separating webs 5 additionally serve as a support for the membrane 3 of the humidifier module 1 or of the humidifier 15 and stabilize the humidifier module 1 or also the humidifier 15.
• FIG. 2 shows an alternative embodiment in which the channels 6 running between the hygroscopic separating webs 5 experience multiple deflections 8.
• deflectors 8 are formed along the longitudinal extent of the separating webs 5 at regular intervals from one another, where the individual separating webs 5 are arranged parallel to one another.
• guide 8 provide areas on which liquid droplets can be deposited so that the fluid flowing past in the channels 6, the liquid water can be removed and received in the hygroscopic separators 5 and temporarily stored therein.
• FIG 3 shows a fuel cell system 2 with a humidifier 15 for humidifying a gas.
• the humidifier 15 has two end plates, not shown, on which an inlet 14 for dry gas, an outlet 18 for humidified gas, another inlet 17 for humid gas and another outlet 13 for dehumidified gas is formed.
• a plurality of the humidifier modules 1 described above are arranged between the two end plates.
• the fuel cell system 2 comprises, as a core component, a fuel cell stack 16 which has a plurality of fuel cells (not shown in greater detail) arranged in a stack. Each fuel cell is assigned an anode compartment and a cathode compartment, the anode and the cathode being separated from one another by an ion-conductive polymer electrolyte membrane. Between two such membrane electrode assemblies Orders is also a bipolar plate, not shown, is arranged, which is used to feed the reactants into the anode and cathode spaces and also establishes the electrical connection between the individual fuel cells.
• the fuel cell stack 16 is connected on the anode side to an anode supply line 20 for supplying an anode gas containing hydrogen from an anode reservoir 19.
• the anode operating pressure on the anode side of the fuel cell stack 16 can be adjusted via an actuator 28 in the anode supply line 20.
• Anodenaustrittsei tig an anode exhaust gas line 24 is present, which is fluid-mechanically connected to a fluid-mechanically connected to the anode supply line 20 anode recirculation line 21 for the removal of unreacted anode gas.
• a separator 22 in particular a water separator, is also present in the anode recirculation line 21, the outflow of which is connected to a cathode supply line 30 by means of a liquid supply line 23 upstream of the humidifier 15. This enables the liquid water produced on the anode side to be fed to the humidifier 15.
• the fuel cell stack 16 is connected to a Kathodenzuschreiblei device 30 for supplying the oxygen-containing cathode gas.
• a compressor 26 is arranged in a part of the cathode supply line 30 designed as a dry feed line 11.
• the compressor 26 is designed as a mainly electric motor-driven compressor 26, the drive of which is via an electric motor, not shown in detail, equipped with a corresponding power electronics.
• the cathode gas which was sucked in from the environment, is fed via the compressor 26 to the humidifier 15 by means of the dry supply line 11.
• a second part of the cathode supply line 30 connects the humidifier 15 to the fuel cell stack 16 and conducted humidified cathode gas to the cathode spaces of the fuel cell stack 16.
• liquid water and unreacted cathode gas is routed back to the humidifier 15 via a cathode exhaust line 31, or the unreacted cathode gas (especially the exhaust air) is possibly fed from the cathode compartments 18 of the fuel cell stack 16 to an exhaust system not provided.
• the humidifier 15 also has a humidifier discharge line 32 for discharging dehumidified cathode exhaust gas.
• the liquid supply line 23 can also be fluid-mechanically connected to the cathode discharge line 31 upstream of the humidifier 15. This also enables liquid water to be fed into the humidifier 15, since the exhaust gas is additionally humidified before it enters the humidifier 15 and its humidifier module 1.
• a bypass line 12 which is fluidically connected to the humidifier discharge line 32, can be present downstream of the compressor 26.
• the method for humidifying a gas in a fuel cell system 2 comprises in particular the following steps: First, liquid water is removed from the fuel cell stack 16 and supplied to the humidifier 15. The liquid water is produced during the reaction of the fuel cell, which then leaves the fuel cell stack 16 in the form of the exhaust gas and can be used in the humidifier 15. The liquid can optionally also be supplied on the anode side via the connected liquid supply line 23 which is fluidically connected to the dry supply line 11 and to the cathode discharge line 31. The liquid water together with the cathode exhaust gas flows through the channels 6 of the humidifier modules 1 of the humidifier 15 and is received in the hygroscopic separators 5 and stored between them.
• the separators 5 can be at least partially emptied again by means of evaporation of the liquid water, especially if the humidifier 15 is not provided with further liquid water or at high loads, so that the gas to be supplied to the fuel cell stack 16 can be humidified.
• the partial emptying can take place when the humidity of the membrane 3 falls below a predetermined or predeterminable threshold value. This threshold value could be determined by means of an electrical conductivity of the humidifier 15.
• the liquid water can also be automatically emptied from the dividers 5 in regular time cycles.
• the separating webs 5 are emptied when no liquid water is supplied or cannot be supplied from the fuel cell stack 16, or the fuel cell system 2 operates in an operating mode in which there is a higher water requirement.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Fuel Cell (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=70008471

Family Applications (1)

Country Status (7)

Citations (7)

Family Cites Families (14)

• 2019
  • 2019-04-24 DE DE102019205811.6A patent/DE102019205811A1/de active Pending
• 2020
  • 2020-03-20 WO PCT/EP2020/057714 patent/WO2020216539A1/de unknown
  • 2020-03-20 KR KR1020217033900A patent/KR20210138740A/ko not_active Application Discontinuation
  • 2020-03-20 US US17/605,926 patent/US20220223884A1/en not_active Abandoned
  • 2020-03-20 EP EP20714503.8A patent/EP3959767B1/de active Active
  • 2020-03-20 CN CN202080030709.XA patent/CN113678292A/zh active Pending
  • 2020-03-20 JP JP2021543146A patent/JP2022518279A/ja active Pending

Patent Citations (7)

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